Abstract: Endogenous attention and exogenous attention reflect the top-down and bottom-up regulation mechanism of orientation and focus of attention. Great deal of event-related potentials studies investigated the effect of endogenous and exogenous attention on neural activities. Endogenous attention has been shown to enhance as early as N1component and late P300 component, while whether early P1 component can be enhanced was less consistent; exogenous attention has been found to enhance N1component, P1 component, and late P300 component. It has also been found that endogenous and exogenous mechanisms represent two attention systems that can affect information processing in the brain in distinct ways

Key words: endogenous attention, exogenous attention, ERP studies